Canon has published a new patent application titled Imagine Device” from the Japan Patent Office (not yet published in the U.S.) which demonstrates a method to cool the media cards in the Cinema EOPS lineup. Although the application does not refer to the Cinema EOS models specifically, we can assume that this apparatus will be implemented in the Cinema EOS since the application defines that this solution is being designed to mitigate the heated media card derived from shooting RAW at high-resolution and FPS.
Source: Canon New Patent: Cooling the Cinema EOS Media Cards – Y.M.Cinema Magazine